1. Field of the Invention
This invention relates to patient positioning devices. More specifically, it relates to a combination supportive wedge and aircushion that provides patients with low air loss therapy and/or alternating pressure therapy.
2. Description of the Prior Art
Patients immobilized or who suffer from certain medical conditions can suffer serious destruction of the skin and soft body tissue. This often results in the formation of pressure ulcers, i.e., bed sores. A pressure ulcer is a localized injury to the skin and/or underlying tissue as a result of pressure, shear and/or friction, which causes partial or complete obstruction of the blood flow to the soft tissue. Immobility, heat, moisture, continence, medication, poor nutrition, and certain medical conditions may all contribute to development of pressure ulcers. Pressure ulcers most commonly occur at the bony prominences, including the sacrum, coccyx, heels, elbows, knees, ankles or the back of the head, and often result in chronic wounds. Pressure ulcers are a major cause of morbidity, mortality, and healthcare expense worldwide. In the United States alone, chronic wounds affect approximately 6.5 million patients, with over 1 million new cases of pressure ulcers developing each year. Complications related to pressure ulcers cause an estimated 60,000 deaths and cost over $1.3 billion annually in the United States. Worldwide, approximately 20% of hospital patients develop pressure ulcers each year. However, most pressure ulcers are treatable and even preventable.
Low air loss therapy is used for the prevention and treatment of pressure ulcers as well as other types of wounds, including venous stasis ulcers, surgical wounds, trauma wounds, lower extremity wounds, and diabetic wounds. Low air loss therapy also provides increased patient comfort for burn patients and patients with certain medical conditions such as Multiple Sclerosis or Lou Gehrig's disease. Low air loss therapy reduces skin interface pressure by allowing the patient to rest or “float” on air-filled, perforated cells, while circulating air across the skin of the patient to reduce moisture.
Currently there exist two methods of providing low air loss therapy: (1) fully integrated bed frames, in which the low air loss surface and bed frame are constructed as a single unit; and (2) a mattress replacement system, in which the mattress lays over or replaces the mattress on the bed. Although these systems are beneficial in preventing pressure ulcers, there are several limitations.
First, situations exist in which the source of the pressure to the skin is from something other than the mattress underneath the patient. For example, patients lying on their sides suffer serious problems with skin-to-skin contact (e.g., between the patient's legs), which, in turn, causes pressure, friction, and moisture between the touching skin regions (e.g., legs). As another example, bariatric patients have an increased risk of pressure ulcers and chronic wounds between skin folds (e.g., skin folds in the abdomen or hips) because the weight of the skin folds and the skin-to-skin contact can create forces that enable pressure ulcers to develop.
Second, due to human anatomy, low air loss mattresses do not provide sufficient relief for certain areas, particularly the bony prominaces. For example, even when using a traditional low air loss mattress, a patient may experience sufficient pressure on the heels, sacrum, or other bony prominances to develop pressure ulcers in those areas. Due to this issue, many hospital protocols require caregivers to reposition the patient to attempt to reduce the pressure on the bony prominances. For example, many hospital protocols require caregivers to elevate the patient's heels to relieve pressure to the heels or turn the patient onto his side to relieve pressure to the sacrum. This is conventionally accomplished by placing a traditional pillow or a foam or gel positioning device under the patient's legs to elevate the heels or behind the patient's back to position him on his side. However, this methodology blocks the low air loss mattress's effectiveness and creates a new pressure point between the patient's heels/legs/back and the traditional pillow, foam or gel positioning device.
Third, some patients require very particular positioning. For example, patients who suffer from pulmonary complications due to immobility, such as nosocomial pneumonia or acute respiratory distress syndrome (“ARDS”), experience a greater likelihood of survival if they can be placed in the prone position. Caregivers generally accomplish the positioning using foam or gel positioning wedges. These types of wedges actually create pressure, friction, and moisture along the skin region that is contacting the foam or gel positioning wedge, resulting in an increased risk of development of pressure ulcers. Further, some positions when accomplished with traditional foam or gel positioning wedges cause a risk of development of other types of complications. For example, prone positioning with a foam or gel wedge can result in damage to the facial nerves or blindness.
Fourth, surgical patients often require special positioning during or after the surgical procedure. Patients undergoing surgical procedures, particularly long surgical procedures, are at increased risk of developing pressure ulcers due to increased pressure on the capillaries when a patient is immobile because of sedation. Currently, surgical and post surgical positioning is accomplished using foam or gel positioning devices. These devices can create pressure points between the patient's body and the foam or gel positioning device, causing greater risk to a patient already at risk of developing pressure ulcers due to the surgical procedure.
Fifth, low air loss mattresses are very costly for the user/hospital and only provide low air loss therapy to the portion of the patient's anatomy that comes in direct contact with the mattress and thus provide only incomplete coverage as well.
The prior art has seen various types and configurations of aircushions. Examples include U.S. Pat. No. 1,382,831 to Hilker; U.S. Pat. No. 2,612,645 to Boland; U.S. Pat. No. 3,308,489 to Winkler; U.S. Pat. No. 3,333,286 to Biolik; U.S. Pat. No. 4,528,705 to Greenawalt; U.S. Pat. No. 4,932,089 to Laviero; U.S. Pat. No. 5,113,875 to Bennett; U.S. Pat. No. 5,173,979 to Nennhaus; U.S. Pat. No. 5,497,520 to Kunz; U.S. Pat. No. 5,657,499 to Vaughn, U.S. Pat. No. 5,697,112 to Colavito; U.S. Pat. No. 5,708,999 to Priolo; U.S. Pat. No. 6,684,425 to Davis; U.S. Pat. No. 7,235,057 to LeVert; U.S. Patent Pub. No. 2008/0178390 to DuDonis; U.S. Patent Pub. No. 2009/0000037; and U.S. Design Pat. No. D587,507 to Martin.
However, none of these aircushions are structured or designed for low air loss or alternating pressure therapy to relieve pressure ulcers or other wounds. Further, many of the references do not include supportive (e.g., foam, air cells, etc.) bases for added support when positioning patients. If supportive bases are included, the supportive base directly contacts the patient, which causes a pressure point which could result in further damage of pressure ulcers. Additionally, none of the prior art addresses the patient microclimate, or the air entering the area to help tissue remain dry and cool, which is one of the most significant factors contributing to development of pressure ulcers. Direct contact between any support base and the patient actually teaches away from the current invention.
Accordingly, what is needed is an economic device that can be easily positioned to support patients while still providing low air loss therapy and/or alternating pressure therapy. However, in view of the prior art considered as a whole at the time the present invention was made, it was not obvious to those of ordinary skill in the art how the limitations of the art could be overcome.
All referenced publications are incorporated herein by reference in their entirety. Furthermore, where a definition or use of a term in a reference, which is incorporated by reference herein, is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
While certain aspects of conventional technologies have been discussed to facilitate disclosure of the invention, Applicants in no way disclaim these technical aspects, and it is contemplated that the claimed invention may encompass one or more of the conventional technical aspects discussed herein.
The present invention may address one or more of the problems and deficiencies of the prior art discussed above. However, it is contemplated that the invention may prove useful in addressing other problems and deficiencies in a number of technical areas. Therefore, the claimed invention should not necessarily be construed as limited to addressing any of the particular problems or deficiencies discussed herein.
In this specification, where a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was at the priority date, publicly available, known to the public, part of common general knowledge, or otherwise constitutes prior art under the applicable statutory provisions; or is known to be relevant to an attempt to solve any problem with which this specification is concerned.